System for forging and pressing liquid metal by using ultrahigh-pressure argon

Abstract

The utility model belongs to a liquid metal forging and crystallizing technology, and particularly relates to a system for forging and pressing liquid metal by ultrahigh-pressure argon, which is characterized in that the molecular spacing is greatly reduced when the metal is solidified through the contractility generated when the liquid metal is cooled and solidified and the 360-degree ultrahigh-pressure gas pressure applied by the outside, so that the grain-refined solid metal is formed, and the solid metal is solidified. Comprising an ultrahigh-pressure forging and pressing container 1 and a roasting box 2 which are fast to open and close, a gap exists between the roasting box 2 and the ultrahigh-pressure forging and pressing container 1, a coil pipe 3 used for cooling the temperature in the ultrahigh-pressure forging and pressing container is arranged at the gap, a graphite cover 5 with a one-way valve 4 is arranged above the roasting box 2, a gas guide pipe 6 is arranged on the side wall of the roasting box 2, and meshes 7 are formed in the middle of a bottom plate of the roasting box 2. An upper air inlet of the air guide pipe 6 is movably connected with the one-way valve 4, a lower air outlet of the air guide pipe 6 is communicated with the meshes 7, a support 8 used for installing a mold shell 16 is arranged in the roasting box 2, and a heating and heat preservation device 9 is arranged on the upper portion of the support 8.

Description

Technical Field

[0001] The utility model belongs to liquid metal forging crystallization technology, and in particular relates to a system for forging liquid metal with ultra-high pressure argon gas. Background Art

[0002] The density of cast metal is lower than that of forged metal. Die casting has a higher density, but the structure of die casting is disordered because it has no solidification sequence, making it the worst casting in terms of performance. Extrusion molding also has no cooling sequence and cannot achieve structural consistency. Hot isostatic pressing presses solids and cannot make the product dense, let alone produce fine-grained structure. Utility Model Content

[0003] The purpose of the present utility model is to provide a system for forging liquid metal using ultra-high pressure argon gas. By utilizing the contraction force generated when the liquid metal is cooled and solidified and the 360° ultra-high pressure gas pressure applied from the outside, the molecular distance between the metals is greatly reduced when solidifying, forming a finely crystallized solid metal, thereby greatly improving the various properties of the solid metal. By optimizing the design of the structure and the coordination method, a feasible systematic forging equipment and forging method are achieved.

[0004] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a system for forging liquid metal with ultra-high pressure argon gas, comprising an ultra-high pressure forging container and a roasting box, wherein there is a gap between the roasting box and the ultra-high pressure forging container, a coil for cooling is provided in the gap, a graphite cover with a one-way valve is provided on the top of the roasting box, an air guide tube is provided on the side wall of the roasting box, a mesh is provided on the bottom of the roasting box, one end of the air guide tube is connected to the one-way valve, and the other end is connected to the mesh, a bracket for installing a mold shell is provided inside the roasting box, an insulation device is provided above the bracket, and an air inlet for connecting ultra-high pressure argon gas is provided on the top of the ultra-high pressure forging container.

[0005] Preferably, it further comprises an upper cover, the air port is provided on the upper cover, and the upper cover is lifted and lowered by a cylinder.

[0006] Preferably, the heat-insulating device is a heating coil, and is located at the pouring cup of the mold shell.

[0007] Preferably, it further comprises an ultra-high pressure container, a compressor and an argon tank, wherein the argon tank is connected to the ultra-high pressure container through the compressor, and the ultra-high pressure container is connected to the gas port.

[0008] Compared with the existing technology, the beneficial effects of the present invention are: the present invention uses the powerful contraction force of liquid metal during the transformation from liquid phase to solid phase and the centripetal air pressure in the external direction of 360° to greatly compress the molecular distance of the metal during solidification, thereby forming a fine-grained structure, and the introduction method and pressurization method of ultra-high pressure gas are also combined with the cooling direction and cooling state of the liquid metal, and the liquid metal in the mold shell is timely compensated for shrinkage, thereby ensuring the molding effect of the liquid metal. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a system structure diagram of the utility model;

[0010] Figure 2 This is a schematic structural diagram of the ultra-high pressure forging container of the present utility model.

[0011] Marking instructions: 1. Ultra-high pressure forging vessel; 2. Baking box; 3. Coil; 4. One-way valve; 5. Graphite cover; 6. Air guide tube; 7. Mesh; 8. Bracket; 9. Insulation device; 10. Air port; 11. Upper cover; 12. Cylinder; 13. Ultra-high pressure vessel; 14. Compressor; 15. Argon tank; 16. Mould shell. DETAILED DESCRIPTION

[0012] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0013] The crystal structure of metal materials can be divided into single crystal, columnar crystal, polycrystalline and fine crystal. The so-called fine crystal refers to the very fine grains of metal materials. The premise for the formation of fine crystals in metal materials is that the gaps between molecules / atoms are highly dense.

[0014] However, achieving highly dense gaps between molecules and atoms is the crux of the matter. As we all know, the contraction force of liquid metal during cooling is incredibly strong and astonishing. Basic casting theory dictates a minimum feeding ratio of approximately 1:1-3, based on the size of the product's hot spot. Even with this process, the product can only be guaranteed to avoid coarse grains, porosity, and shrinkage cavities. Liquid metal loses nearly 10% of its volume during cooling and solidification, resulting in an extremely strong contraction force.

[0015] Similarly, diamonds are also formed by crystallization in a high-temperature and high-pressure environment during crustal changes. People have used this principle to invent equipment for artificial diamond production. It is composed of six tungsten-cobalt alloy top hammers. The pressure of the oil cylinder is used to press the six-sided top blocks centripetally onto the catalyst, resulting in an artificial diamond.

[0016] Currently, there are many ways to improve the density of metals in existing technologies. For example, my country has produced an 80,000-ton forging press, which can produce large forgings, but cannot make the material highly dense because it presses solids and applies pressure in a single direction. It increases the density of the material, but cannot achieve the high density effect formed when the liquid transforms into a solid. In addition, there is the hot isostatic pressing method, which places the material in an ultra-high pressure container and heats it. The product is forged 360 degrees using ultra-high pressure argon gas. Because it uses gas pressure, it does not destroy the product structure, thereby increasing the material density and improving the product's physical and chemical properties.

[0017] In order to improve the performance of materials, people selectively combine and melt metals and non-metals, try to develop formulas to improve material performance, and add elements such as niobium and molybdenum to refine the grains. However, fine crystals cannot be formed, and the various properties of the materials cannot be significantly improved.

[0018] After the formation of fine grains, the metal material's heat resistance, corrosion resistance, erosion resistance, wear resistance, tensile strength, and elongation will be rapidly improved. Its functional design, safety performance, and service life will also have a qualitative leap.

[0019] Regarding the background technology, ultra-high-pressure argon forging liquid metal, also known as precision casting heating and isostatic pressing, ensures the principles of sequential cooling and solidification in precision casting, ensuring structural consistency. When the liquid metal is cooled and solidified from the liquid state and pressurized, the distance between the molecules of the liquid metal is reduced due to its free state. At the same time, the pressure of the ultra-high-pressure argon gas is applied. This further reduces the distance between the molecules, forming a highly dense structure, which in turn reduces the grain size and ultimately produces a fine-grained structure.

[0020] The technical solution of the present invention includes a system for forging liquid metal with ultra-high pressure argon gas, comprising an ultra-high pressure forging container 1 with quick opening and closing and a roasting box 2, wherein a gap is provided between the roasting box 2 and the ultra-high pressure forging container 1, a coil 3 for cooling the temperature in the ultra-high pressure forging container is provided in the gap, a graphite cover 5 with a one-way valve 4 is provided above the roasting box 2, an air guide pipe 6 is provided on the side wall of the roasting box 2, a mesh 7 is provided in the middle of the bottom plate of the roasting box 2, an upper air inlet of the air guide pipe 6 is movably connected with the one-way valve 4, and a lower air outlet is connected with the mesh 7. After passing through the mesh 7, the bottom of the blow mold is cooled, forcing the liquid metal in the mold to be cooled and pressurized from bottom to top, forcing the metal liquid to follow the principle of sequential cooling and sequential crystallization) the roasting box 2 is provided with a bracket 8 for mounting the mold, a heating and heat preservation device 9 is provided on the upper part of the bracket 8, and an air inlet pipe 10 is provided on the upper cover of the ultra-high pressure forging container 1; the power supply is introduced from the ultra-high pressure forging container cover and connected to the heating and heat preservation device through the graphite cover.

[0021] The entire operating system of ultra-high-pressure argon forging liquid metal is controlled automatically by electricity and can also be controlled manually. The control target is: argon forging liquid metal starts from low temperature and low pressure, with smooth buffering, and gradually cools and pressurizes until it reaches high pressure. The liquid metal molecules are in a free state. Through cooling and pressurization, the distance between molecules begins to shrink when the liquid metal cools. The ultra-high-pressure argon plays a role in fueling the process. The compression force plus the pressure of ultra-high pressure 360-degree pressure. Under the pressure of the superposition of these two forces, the distance between molecules is further reduced, the density is further increased, the crystal grains are also reduced, and a fine-grained structure is produced. At this point, the material's heat resistance, corrosion resistance, wear resistance, erosion resistance, tensile strength, and elongation will be geometrically improved.

[0022] The air intake duct 10 is provided on the upper cover 11 , and the upper cover 11 is lifted and lowered by a cylinder 12 .

[0023] The heat preservation device 9 is a heating coil and is located at the pouring cup of the mold shell.

[0024] It also includes an ultra-high pressure container 13 , a compressor 14 and an argon tank 15 . The argon tank 15 is connected to the ultra-high pressure container 13 through the compressor 14 , and the ultra-high pressure container 13 is connected to the air inlet pipe 10 .

[0025] The utility model is an understanding and combination of the two processing technologies of ultra-high pressure argon forging liquid metal and forging. When the metal is in liquid state, the metal molecules are in a free state. The liquid metal in the mold shell 16 is placed in the baking box 2. Under the forging pressure of ultra-high pressure argon gas and in the state of self cooling and shrinkage, the distance between the metal molecules is naturally contracted. Combined with the centripetal pressure of the ultra-high pressure gas in all directions of 360°, the distance between the metal molecules is artificially reduced under the superposition of the two forces of metal shrinkage and gas pressure, forming a highly dense grain. Small, forming a fine-grained structure. Forging, on the other hand, involves heating and forging solid metal in a single direction. The metal molecules are no longer in a free state, and the distance between them is already stable. Even heating and pressurizing cannot completely change the spacing between metal molecules. Furthermore, unidirectional forging will only tear metal fibers and destroy the metal structure. However, the structure of liquid metal forged with ultra-high-pressure argon gas is complete and uniform because the gas pressure is based on the 360-degree centripetal pressure of the liquid metal. Furthermore, since the metal molecules are in a free state and the pressure on them is equal, the structure is complete and uniform. This also reduces the distance between metal molecules in a complete and regular manner. This is the fundamental difference between forging and ultra-high-pressure argon gas forging of liquid metal.

[0026] The ultra-high-pressure argon liquid metal forging method of the present utility model comprises:

[0027] Step 1: The argon tank 15 pressurizes the argon gas through the compressor 14 and stores it in the ultra-high pressure container 13;

[0028] Step 2: Open the upper cover 11 and the graphite cover 5 through the cylinder 12, and place the mold shell with liquid metal into the bracket 8 of the roasting box 2. The mold shell itself has very dense pores, which can keep the gas connected with the inside and outside of the mold shell, and the metal liquid cannot flow out from the inside of the mold shell. The heat preservation device 9 is used to keep the pouring cup of the mold shell warm. At this time, the metal in the mold shell is in liquid state.

[0029] Step 3: Cover the graphite cover 5 on the baking box 2, keep the one-way valve 4 of the graphite cover 5 connected to the air guide pipe 6 of the baking box 2, and then cover the upper cover 11 on the ultra-high pressure forging container 1 through the cylinder 12;

[0030] Step 4: When the metal in the mold is in liquid state, the ultra-high pressure container 13 starts to pressurize through the air inlet pipe 10. After the ultra-high pressure argon gas enters the ultra-high pressure forging container 1, it is first located above the graphite cover 5. First, the graphite cover 5 can block the high pressure argon gas entering to achieve a buffering effect, thereby effectively protecting the mold and the liquid metal in the mold from being damaged by the high pressure argon gas that is pressed in instantly, and making the gas pressure on the outer wall of the liquid metal in the mold stable and gradually increase; secondly, when the low temperature argon gas under the graphite cover meets the high temperature of the liquid metal in the mold, the graphite cover 5 The gas pressure below will be instantly increased. At the same time, the graphite cover 5 itself is air-permeable, which can reduce the pressure difference between the top and bottom of the graphite cover 5 and prevent the graphite cover from being lifted or displaced. Moreover, since graphite itself has heat resistance and heat preservation properties, the temperature above the graphite cover 5 is always kept at a low temperature, thereby effectively protecting the structure and seals above the graphite cover 5. In addition, the pressure outside the mold shell is changed from a boosting state to a holding state, thereby providing a stable 360° centripetal pressure for the liquid metal in the mold shell during the process of transitioning from liquid phase to solid phase.

[0031] While keeping the graphite cover 5 and the baking box 2 sealed, the upper part of the ultra-high pressure forging container 1 is gradually filled, and further passes through the one-way valve 4 on the graphite cover 5 and the air guide pipe 6 into the bottom of the baking box 2;

[0032] Step 5: After passing through the mesh 7, the argon gas from the air guide pipe 6 pressurizes and cools the liquid metal in the mold from the bottom up. Since the pouring cup of the mold 16 is located above the mold, the liquid metal in the mold is cooled from the bottom up, and a metal shell with a certain hardness is formed on the outside during the cooling process. The direction of the ultra-high pressure argon gas is the same as the solidification direction of the liquid metal, providing further ultra-high pressure 360° to the hard metal shell.

[0033] Step 6: When the liquid metal cools in the mold shell and changes from liquid to solid, the contraction force of the metal during cooling and the pressure of the ultra-high pressure gas jointly form a highly dense, fine-grained solid metal from the free liquid metal;

[0034] Step 7: During the solidification process of the liquid metal in the mold, the heat preservation device 9 always keeps the pouring cup of the mold warm, so that the metal in this part is in a liquid state, providing real-time shrinkage compensation for the solidification process of the metal in the mold; the liquid state is maintained for 4 to 5 minutes. After 5 to 15 minutes, the liquid metal is cooled and pressurized. Under the superposition of the two pressures of cooling and solidification shrinkage and ultra-high pressure argon gas (metal shrinkage and ultra-high pressure gas pressure), the metal becomes highly dense (the precision casting mold has a certain degree of air permeability), the distance between molecules is reduced, the crystal phase structure is reduced, and a fine-grained structure material is produced, so that various physical and chemical properties are rapidly improved; the container releases the pressurized gas one by one into the multi-stage pressure vessel, and finally enters the atmosphere at low pressure;

[0035] Step 8: After the liquid metal in the mold shell 16 is transformed from a free state into a fine-crystalline solid, the argon gas in the air inlet pipe 10 is discharged into the ultra-high pressure container 13 again.

[0036] During the cooling process of the liquid metal, a cooling medium is introduced into the coil 3 to further realize the controllable cooling speed of the metal in the mold shell 16. There are several ultra-high pressure containers 13. In the pressurization stage in step 4, a gradient pressurization is adopted to gradually increase the pressure in the ultra-high pressure container during the gradient process. In this way, it can be ensured that the external gas pressure is also rising synchronously when the outer surface of the metal in the mold shell is gradually hardened. Otherwise, when the outer shell of the metal in the mold shell is soft, a higher air pressure is suddenly introduced, which will pressurize the liquid metal in the entire mold shell into droplets. In the decompression stage in step 8, a gradient decompression is adopted to gradually reduce the pressure in the ultra-high pressure container during the gradient process. The purpose of this is to protect the seals and pipelines in the entire ultra-high pressure forging container 1. Finally, the ultra-high pressure container is opened and the casting product is taken out.

[0037] The entire internal system of the container, including the graphite cover, pipelines, baking box and insulation device, can ensure that the liquid metal is cooled and solidified sequentially from bottom to top, thereby achieving consistent crystallization.

[0038] The graphite cover has heat-resistant, heat-insulating and breathable properties, which protects the upper sealing ring of the graphite cover to work at a lower temperature, buffers the pressure of the gas on the mold shell, and can balance the pressure above and below the graphite cover.

[0039] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A system for forging liquid metal with ultra-high pressure argon gas, comprising an ultra-high pressure forging container (1) with a quick opening and closing mechanism and a roasting box (2), wherein a gap exists between the roasting box (2) and the ultra-high pressure forging container (1), and a coil (3) is provided in the gap for cooling the temperature in the ultra-high pressure forging container, characterized in that: A graphite cover (5) with a one-way valve (4) is provided above the roasting box (2), an air guide pipe (6) is provided on the side wall of the roasting box (2), a mesh hole (7) is provided in the middle of the bottom plate of the roasting box (2), an upper air inlet of the air guide pipe (6) is movably connected to the one-way valve (4), and a lower air outlet is connected to the mesh hole (7), a bracket (8) for mounting a mold shell (16) is provided inside the roasting box (2), a heating and heat preservation device (9) is provided on the upper part of the bracket (8), and an air inlet pipe (10) is provided on the upper cover of the ultra-high pressure forging container (1).

2. The system for forging liquid metal with ultra-high pressure argon as claimed in claim 1, characterized in that: It also includes an upper cover (11), the air intake pipe (10) is arranged on the upper cover (11), and the upper cover (11) is lifted and lowered by a cylinder (12).

3. The system for forging liquid metal with ultra-high pressure argon as claimed in claim 1, characterized in that: The heat preservation device (9) is a heating disk resistance wire and is located around the pouring cup of the mold shell (16).

4. The system for forging liquid metal with ultra-high pressure argon as claimed in claim 1, characterized in that: It also includes an ultra-high pressure container (13), a compressor (14) and an argon tank (15), wherein the argon tank (15) is connected to the ultra-high pressure container (13) through the compressor (14), and the ultra-high pressure container (13) is connected to the air inlet pipe (10).

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